Metal extrusion presses with rotary die-holder carriers

ABSTRACT

In a metal extrusion press having a rotary die-carrier, stabilizing means for the die carrier, comprising a clamping device consisting of a pair of retractable jaws adapted to engage opposite sides of the die-carrier.

United States Patent 1 1 3,589,162

[72] Inventors Ernest Lamas; [56] ReferencesCiued I N ggtseagisnglelon, both of Dorset, England UNITED STATES PATENTS qlfd DQ61 3,391,564 7/1968 Linnerz 72/268 [45] Named 5 971 3,357,226 12/1967 5116116161. 72/263x 1 3,127,014 3/1964 Dohmetal 72/263X ml 'img 3,175,384 3/1965 065656161. 72/263x 3,124,250 3/1964 Krause 72/263 [32] Prior ggf g gg'g 3,359,770 12/1967 ASal'i 72/263x [33] y Gre'atBrimin 3,197,994 8/1965 5611111616161. .1 72/263 [31] 553" 3,364,719 1/1968 ASal'l 72/255 Primary Examiner-Richard J. l-lerbst Assistant Examiner-Michael J. Keenan Attorney-Hammond and Littell [54] METAL EXTRUSION PRESSES WITH ROTARY DIE-HOLDER CARRIERS 3 Claims, 4 Drawing Figs. [52] U.S.Cl 72/263 ABSTRACT: In a metal extrusion press having a rotary die- [51] Int. Cl B2lc 23/00 carrier, stabilizing means for the die carrier, comprising a [50] Field of Search 72/263, clamping device consisting of a pair of retractable jaws 255; 207/ l .1 adapted to engage opposite sides of the die-carrier.

PATENTED JUN29 197:

sum 1 or 4 Er t Lev mad) P6 llorney PATENTEUJUN29I97I 3.589162 SHEET 2 GP 4 Fig.2.

E algmzrilors m? m Peter Singleton QMWA/ZEZ/ Attorney METAL EXTRUSION PRESSES WITH ROTARY DIE- IIOLDER CARRIERS This invention relates to a metal extrusion press with a rotary carrier for one or more dies. The die-carrier is rotatable in a plane transverse to the main press axis along which the extrusion of billets from a container through a die takes place. In this way, the die-carrier can be moved from a position in the main press axis into a position outside this axis in which the die can be exchanged or cleaned, cooled, lubricated or otherwise prepared for an extrusion operation.

In all extrusion presses in which a product is extruded from a billet through a die, it is necessary, after an extrusion operation, to sever the unextrudable portion of a billet-the billet discard-from the extruded product. This operation is frequently carried out by means of a shear or saw whose blade moves across a face of the die-carrier and cuts through the extruded article.

In metal extrusion presses of the type described, container and die are movable relative to each other and to a platen on which the die is axially supported during an extrusion operation, so that the required clear space for the movement of the discard-cutting blade across the face of the die-carrier is obtained. The die-carrier is then in an unstable position in its plane of rotation. This instability of the die-carrier is a drawback, particularly during a discard-severing operation. The die-carrier is apt to yield to the shearing force duringrcutting, and to swing about its pivot so that it becomes difficult to obtain a clean and square cut. The instability of the die-carrier may also make it difficult to align the die with the container before the two are moved in contact with each other in readiness for an extrusion operation.

It is therefore an object of the present invention to provide a metal extrusion press having a'rotary die-carrier with retractable means for stabilizing the die-carrier and thereby preventing rotation of the carrier when not desired.

An embodiment of the invention will now be described by way of example with reference to the accompanying drawings, in which:

FIG. 1 is a vertical section along line H of FIG. 2 through the container end of the metal extrusion press according to the invention.

FIG. 2 is a vertical section along line II-[l of FIG. 1.

FIG. 3 is a section corresponding to that of FIG. 1 showing a further embodiment of the invention.

FIG. 4 is a section corresponding to that of FIG. 1 showing a still further embodiment of the invention.

The press shown in the drawings is of the horizontal type and comprises a platen which is connected by means of four parallel columns 12 to the main cylinder, not shown. Ar ranged in the main axis X-X of the press is a die-assembly 16 which comprises the die proper 18, die-holder l9 and two pressure rings 20 and 22. The die-assembly is seated in a U- shaped recess of a die-carrier 24, as clearly seen from FIG. 1, so that the assembly can be laterally removed from the diecarrier as a whole and inserted therein.

The die-carrier 2 4 is substantially in the shape ofa flat plate and has a U-shaped recess at each end for the accommodation of die-assemblies 16, of which only one is shown in FIG. 1. The carrier 24 can be rotated, by means not shown, about a pivot pin 26 which is in the same horizontal plane as the axis X-X and parallel to the latter. By rotating the die-carrier 24 by 180, the two die-assemblies 16 exchange their positions with each other relative to the main press axis XX so that the assembly which was previously in this axis is now at an outside station, and vice versa.

Arranged between the die-carrier 24 and the platen 10 is a bolster ring 28 which supports the die-carrier 24, and thereby the die-assembly which is in the press axis, on the platen 10.

Arranged in front of the die-assembly is a billet container 30 mounted in a housing 32, the latter being displaceable in the direction of the axis XX by means of cylinders, not shown, through push rods 34.

The press is operated in the I'lOl'IIllfll manner in that billets received in a chamber inside the container 30 are extruded through the die 18 into a product which leaves the press through a tunnel 36 in the platen III, the extrusion being effected by. means ofa pressing stem, not shown, actuated by the main ram.

As is well known in the art of extrusion, it is necessary, after each operation, to sever the extruded product from the unextrudable remainder of the billetthe billet discard. This is effected in the press according to the invention by means of a shear having a blade 38 mounted on a shaft 40 guided in an extension 42 of platen 10. The shaft is moved up and down by means of a hydraulic ram, not shown. Previous to a discardshearing operation, the container 30 is moved away from the die 18 by means of the push rods 34 so that a clear space is obtained between die and container into which the blade 38 can enter for discard-shearing.

The design of the metal extrusion press so far described follows conventional lines.

According to the present invention, there are provided in the press means for stabilizing the die-carrier 24 against unintended rotary movement. The latter may otherwise occur, for instance, when the die-carrier is not firmly held in position by the close contact between container 30 and die 18 at one side and between die-carrier 24 and bolster ring 28 at the other side, as is the case during extrusion of a billet. Unintentional rotary movement can thus occur when the shear blade 38 descends for a cut, or ascends thereafter. Movement of the die-carrier and thereby also of the die 18 at this stage is undesirable, as this makes it difficult for the blade 38 to make a clean and square cut.

According to the invention, there is provided a clamping device for the die-carrier 24, the device comprising a pair of jaws, an upper jaw 44 which acts on one of a pair of inserts 46 in the die-carrier, and a lower jaw 481 which acts on one of a pair of inserts 50 in the die-carrier. The jaws 44 and 48 are both arranged in the vertical plane through the axis X-X. The inserts of each pair are arranged diametrically opposite each other with respect to the axis of the pivot pin 26, so that one of the inserts 46 faces the jaw 44 and one of the inserts 50 faces the jaw 48 when the die-carrier 24 is in an angular position in which one of the die-assemblies 16 is in the axis X-X of the press. Thus there is always an insert 46 ready to cooperate with the jaw 44 and an insert 50 ready to cooperate with the jaw 48 when a die-assembly 16 is in the axis X-X. In the position of the press shown in FIG. 1, one of the inserts 46 and one of the inserts 50 are in the vertical plane through the axis XX.

The jaw 44 is formed at the end ofa rod 52 which can be advanced or retracted by means of a hydraulic unit 54. The jaw 48 is wedge shaped and operated by a hydraulic cylinder-andpiston unit 56 mounted on a bracket 58 secured to the lower part of the platen 10 by means of bolts 60. The jaw 48 has a guideway 62 on the bracket 58 and is connected by a rod 64 to the ram, not shown, of the unit 56. The inserts 50 have inclined surfaces so that they can cooperate with the wedgeshaped jaw 48.

When it is desired to rotate the die-carrier 24 about its pivot pin 26, the wedge-shaped jaw 48 is withdrawn to the left in FIG. 1, and the jaw 44 raised so as to clear the path for the movement of the die-carrier. During extrusion of a billet, the jaws 44 and 48 may be in their clamping position, although this is not necessary. However, while discard-severing is in progress, the twojaws 44 and 48 should be in contact with the inserts 46 and 50 respectively, as shown in FIG. 1, whereby the die-carrier 24 is firmly held against rotation in either direction, and a clean and square cut ensured. At the same time, the pivot pin 26 is relieved from the shearing torque.

The press shown in the embodiment according to FIG. 3 is similar to that of the embodiment according to FIGS. 1 and 2, except for the clamping device provided for its die-carrier 24. In the embodiment according to FIG. 3, the clamping device for the die-carrier 24 comprises an upper jaw 44 which acts on one of a pair of inserts 46 in the die carrier, and a lower jaw 144 which acts on one of a pair of inserts 146. The inserts 46 and 146 are arranged on the die-carrier in a manner similar to the inserts 46 and 50, so that there is always an insert 46 ready to cooperate with the jaw 44, and an insert 146 ready to cooperate with the jaw 144 when one of the die-assemblies 16 is in the axis X-X.

The jaw 44 is formed at the end of a rod 52 which can be advanced or retracted in a stationary tubular guide 53 by means of a hydraulic unit 54. The jaw 144 is formed at the end of a rod 152 which can be advanced or retracted in a stationary tubular guide 153 by means ofa hydraulic unit 154.

The clamping device according to FIG. 3 differs therefore from that according to FIGS. 1 and 2 in that the lower jaw 48, the lower inserts 50, and the parts 56 to 64 have been replaced by ajaw-assembly which is similar to the assembly of the jaw 44.

The press shown in the embodiment according to FIG. 4 is again similar to that of the embodiment according to FIGS. 1 and 2, except for the clamping device provided for the die-carrier 24. In the embodiment according to FIG. 4 this clamping device comprises a lower jaw 48 which acts on one of a pair of inserts 50 in the die-carrier, and an upper jaw 148 which acts on one of a pair of inserts 150. The inserts 50 and 150 are arranged on the die-carrier in a manner similar to the inserts 46 and 50 of the first embodiment so that there is always an insert 50 ready to cooperate with the jaw 48, and insert 150 ready to cooperate with the jaw 148 when one of the two die-assemblies 16 is in the axis X-X.

The jaws 48 and 148 are wedge shaped and operated by hydraulic cylinder-and-piston units 56, 156 respectively mounted on brackets 58, 158 respectively secured to the platen by means of bolts 60, 160. The jaws 48 and 148 are movable along guideways 62, 162 respectively on the brackets 58, 158 respectively and they are connected by rods 64, 164 respectively to the pistons, not shown, of the units 56, 156 respectively. The inserts 50, 150 have inclined surfaces so that they can cooperate with the wedge-shaped jaws 48, 148.

The operation of the embodiment of FIGS. 3 and 4 is similar to that of the embodiment shown in FIGS. 1 and 2, with the jaws being in their clamping positions when discard-severing is in progress and, if desired, also during the extrusion of a billet.

In all three embodiments, adjustment means are preferably provided for ensuring that the die-carrier 24 is, during extrusion, in a position in which the extrusion die 18 is in alignment with the main press axis X-X. This may be achieved by the use of shims placed between the inserts and the die-carrier 24. Alternatively, as shown in FIG. 3, adjustable locking nuts 166 may be used which are threaded on to the rod 152. These adjustment means become effective when the jaws of the clamping device are moved in contact with their associated inserts.

It will be seen from the foregoing that in all three embodiments the actuating means for the jaws are arranged above and below the die-carrier, thereby avoiding any obstruction at the side ofthe press.

We claim:

1. A metal extrusion press having a main axis, a rotary diecarrier adapted to be rotated in a plane transverse to the main axis, and retractable means for stabilizing said die-carrier and preventing its rotation, in which said retractable means com prise a clamping device consisting of a pair of independently actuated retractable jaws which are movable in a straight line and in a direction radial to the main axis and which engage opposite sides of the die-carrier at points situated diametrically opposite each other with respect to the main axis, for arresting said die-carrier in a position in which a die in said carrier is in the main axis of the press, said die-carrier being free to rotate after retraction of said jaws.

2. A metal extrusion press according to claim 1, in which a wedge is provided, said wedge being displaceable in a tangential direction relative to the main axis of the press, the inclined surface of said wedge being in engagement with a matching inclined surface on one of said jaws, so that by displacement of said wedge in a tangential direction, said jaw is moved in a direction radial to the main axis of the press.

A metal extrusion press according to claim 1, in which said jaws and their actuating means are arranged above and below the die-carrier respectively. 

1. A metal extrusion press having a main axis, a rotary diecarrier adapted to be rotated in a plane transverse to the main axis, and retractable means for stabilizing said die-carrier and preventing its rotation, in which said retractable means comprise a clamping device consisting of a pair of independently actuated retractable jaws which are movable in a straight line and in a direction radial to the main axis and which engage opposite sides of the die-carrier at points situated diametrically opposite each other with respect to the main axis, for arresting said diecarrier in a position in which a die in said carrier is in the main axis of the press, said die-carrier being free to rotate after retraction of said jaws.
 2. A metal extrusion press according to claim 1, in which a wedge is provided, said wedge being displaceable in a tangential direction relative to the main axis of the press, the inclined surface of said wedge being in engagement with a matching inclined surface on one of said jaws, so that by displacement of said wedge in a tangential direction, said jaw is moved in a direction radial to the main axis of the press.
 3. A metal extrusion press according to claim 1, in which said jaws and their actuating means are arranged above and below the die-carrier respectively. 